Ignition system for gas-engine dynamo sets.



IGNITIQiT SYSTEM FOR GAS ENGINRDYNAMO SETS.

AAPPLIGATION FILED MAR. 29-, 1910. H

994,288. Pat ntedJune6,1911.

UNITED sra rns PAT NT OFFICE.

nemon'r MAX rennin, or NEWTON CENTER, massaoircsnrrs', ASSIGNOR 'ro nor-ram 'CABOT ELECTRIC COMPANY, or BROOKLINE, massacnosnr'rs', a CORPORATION 01 MASSACHUSETTS.

IGNITION 'sYsrEM rogues-ENGINE ynamo snrs.

asubject of the. Emperor of Germany, and

a residentof Newton Center, in the county of Middlesex and State of Massachusetts,

have invented a new and useful Improvement 'in-Ignition Systems for Gas-Engine Dynamo Sets, of which the following .18 a

specification.

Heretofore it has been the practice to v fem-ploy'a magneto-generator to energize the ignition dev ces of gas-engines which "are employed to drive electric generators, such magneto-generators being driven by the engine. This arrangement, however, is ob- JGCtlOIIablQ because of ncreasedfirst cost and cost of maintenance, thevlife ofv the magneto-generator being limited.

It is therefore the object of the present invention to ptov'ide a simplified ignition systemin which the magneto-generator hereto-- fore employed is eliminated and the current I for energizing the sparking-apparatus is ob-- tained directly from the electric generator which is mounted on the shaft of the gas 'engine'or otherwise driven thereby.

In carrying out my invention, 1- find 1t desirable in cases where the windin s of the spark coil are conductively connects to proerator leads becoming grounded, and to provide other means whereby the generator cannot become short-circuited through. the timer under similar conditions. It is also desirable that said protective resistance be arshown in diagram several examples of ap- 4 5..

ranged in a member which serves as a coupling between the timer and the shaft which drives the same so thatit cannot readily be removed. v

In'the drawings which accompany and form a part of this specification,- I have parat-us and circuit arrangements whereby .the foregolng ob ects have been realized in l practice; but it willjbe understood that various modifications may be .made both in the apparatus and "circuit-arrangements w thout departing from the pr nciple-of my invention. a K 7 g Figure 1 is a diagram showing one embodiment of my improvedligmtion system 'lation I interposed'between the timer and spark-coil are conductivel connected. Fig.-

2 is a diagram showing t e preferred form Specification orletter'sfatenta Y t f d Jun 6,1 1 Application filed March- 29, 1910. Serial'No. 552,126. I 3 i of my i nvention,--and Fig.3 IS an elevation, partlyin section, of one formof protective device.

- In the drawings which I have selected for illustrating y invention, A- represents a' spark-plug, one terminal of which is grounded in the usual manner on the gas-engine cylinder '13. In Fig. 1 the spark-plug is connected with the secondaryS of the spark COll and said secondary is conductively connected to the primary P. The spark-coil and spark-plug constitute the spark-prothe same is completed through the vibrator V, timer T and protective device L, which'as ,ducing apparatus, and the circuit through brush 'B so related to one of the usual brushes as B and adjustable with respect.

thereto, that any small difference of-potendeveloped across the terminals of said -tial desired, for example, six volts, will be brushes B, B", and to connect the primary,

of the spark-coil and the timer in series with saidbrushes' The main brushes B, B of i l I the generator are connected respectively to the external circuit C, C.

, Inasmuch as the timer in'the usual igni tion systems, which are energized by magneto-generators or other sources of current independent of the generator driven by the gas-engine, is grounded on the gasrengine, it

follows that in the arrangement shown in Fig. 1 the generator willbe short circuited through a timer so grounded if one of the 'leadsG C'to the external circuitbecomes grounded. Accordingly it is desirablevin my system to insulate the timer fromthe engine, and this may be done 'in-any suitable manner. as indicated in Fig. 1 by the insutective resistance L is to prevent injury to the armature windings of the generator in the event of one of the leadsC C becoinin' grounded. If the protective resistance were not employed and-stheleadicshould- .of the secondary current in Fig. '1 is romone terminal of the secondar Sp-to -A, the.

become grounded, an -excessiverise-of rent would occur iu-the circuit B, Y, Z, B B; and should the 'leadG f-1-l grounded under similar conditions, -"suchie cessive rise of current-would occuriiiflthe circuit B C E, X, Y, Z, B" B The filth spark-gap .ofthe plug, E, X, Yan'd thence back to the other terminal of. the' secondary by two paths, one of whichis the come opened, as for instance by the removal.

path YT F V P- to S and the other path Y Z B" B toS. Should the L X Ycircuit between the spark-plug and the timer beof the resistance L, the insulationof the generator would be subjected to the full potential of the seeo nda'ry- S resulting in the breakdown of the same. "This will be readily understood when it is noted that the" generator frame, journals, armature shaft, and "armature core, are all in metallic contact with the engine frame and the'en- --ondar a. seeon ary 0011 ,S is conductively connected gine cylinder." The latter, represented; at E, -is conductively connected through the spark-plug with one terminal of the, seccoil S. The other'terminal of the to the armaturewinding through the brush I B'..'*a' .Thus'betweenthe armature core and the armature winding there would exist (were the circuit L 'X Y opened) a very high potential (such for example as 20,000 volts) with the result that the insulation of thearm'ature winding, which is interposed between said winding and core, would be ruptured. The circuit L X Y connects E.

with-the other terminal of the secondary coil S through the timerand the low-resistance.

rimary (the path Y T F V P, about re-,

' erred to) and through a portion of the armature'winding (the 'path Y Z B B, above-referred to) and thus closes the otherwise open circuit of the secondary, thereby preventing the excessive rise of pressure across the generator insulation. Accordingly, as shown in Figs. 2 and 3, I prefer to so arrange the rotective resistance L that it cannot readi y be removed to open' said circuit. In the present case the timer T issecured in any suitable manner as by the screw U to the stud Q, of a member herein shown as a casing which supports the protective resistance L and which in turn is secured to the shaft'D by the screw WJ The insulating bushing I is interposed be tween the shaft D and the member which carries the resistance L. The terminals of said resistance are connected respectively to the portion M of the casing and to thering O, and the latter is electrically connected to the shaft D by the screw-IV which passes through theinsulation I and contacts with said shaft. For simplicity the timer is secondary S, which includes the spark-plug A, is-completed through the" engine E to the shaft D, ring 0, high resistance protective resistance L, and easing M. It w'll be noted that while a user of th apparatus might disconnect or short-circuit the resistance L in the simple arrangement shown in Fig. 1, the said'resistance could not readily .be. removed in thearrangement shown in Figs. 2 and 3; Shouldthe casing- M, which carries the high resistance between the timer and the shaft which drives the same, be removed, and the timer placed directly on said shaft,'the resulting arrangement would be identical with that shown in Fig. 1 if the circuit L X Y were removed and the insulation I. eliminated. f In other words, .such removal of the ,cou-

pling'and the protective resistance contained rotective device and which serves as a coup ing therein would produce a system the defects of which it is the objectof my invention to overcome.

I claim: 1. In an ignition system for a gas-engine dynamo set, a spark-producing apparatus for the gas-engine, said spark-producing apparatus comprising aspark plug, a timer, a shaft driven by the engine for driving" said'timer, a dynamo, means for diverting a portion of the current from said dynamo to energize said spark-producing apparatus, a

protective resistance connected in the' cir cuit of said spark-producing apparatus between said spark plug and timer, and a member' carrying said protective'resistance and serving as a coupling between said timer and said shaft. I

2. In an ignition system for a gas-engine dynamo 'set, a spark-producing apparatus for the gas-engine, said spark-producing apparatus comprlsmg a spark plug, a tlmer, a

shaft driven by the engine for driving said timer, a'protective resistance connected in the circuit of said spark-producing apparatus between said spark plug and timer,

and a member carrying said protective resistance and serving'as a coupling between said timer and said shaft. I

3. In an ignition system for a gas-engine dynamo set, a spark-producing apparatus for the gas-engine, said spark-producing apparatus comprising a spark-plug, a timer, a

shaft driven by the engine for driving said timer, a protective resistance connected in the circuit of said spark-producing appara-' .tus between said spark plug and timer, .and

a member inclosing said rotective resistance and serving as a coup ing between said timer and said shaft.

. ,4. In an ignition system for a'gas-engine dynamo set, a member connected and arranged to serve as a coupling between a gasengine-timer and the shaft of the engine which drivessuch timer, said member being provided withmeans for insulating the same from such shaft, means whereby a timer may be secured to said member, and a circuitprotective resistance carried by saidmember.

5. In an ignition system for a dynamo set, a member connecte I ranged to serve as a coupling between a gas- (gas-engine engine-timer and theshaft of the engine which 'drives such timer, said member being provided with means for insulating the same from such shaft, means whereby a timer may be secured to'said member, and a circuit protective-resistance inclosed within said member. t

6. In an ignition system'for a gas-engine dynamo set, a timer, an engine-driven shaft for driving said timer, a member connectedv and arranged 'to serve as a con ling between said timer and shaft, said mem er being provided with means for insulating the same from said shaft, means whereby said timer may be secured to said member, and a circuit -pr0tective resistance carried by said member.

7. In an ignition'system for a gas-engine dynamo set, a timer, an engine-driven shaft for'driving said timer, a member connected and arranged to serve as a coupllng between 1 said timer and shaft, said member being provided. with means for insulating the same from said shaft, means whereby said timer may be secured to said member, and a circuit-protective resistance inclosed within said member. v

8. In an ign1t1on system for a gas-engme dynamo set, aspark-producing apparatus for the gas-engine, said spark-produc1ngap'- paratus comprising a sparklug, a timer, a shaft driven by the engine f br driving said timer, a dynamo,means for diverting a por tion of the current from said dynamo to energize said spark-producing apparatus, a 5.0 protective resistance connectedin the circuit of said spark-producing apparatus between said spark-plug and dynamo and a member carrying sald ,protectiveresistance and serving as a coupling between said timer and said shaft. and ar for the gas-engine, said spark-producing app- .76

paratus comprising a sparklug, a timer, a shaft driven by the engine ordriving said timer, a protective resistance connected 'in the circuit of said spark-producing apparatus between'said spark-plu .and'dynamo, and a member inclosing sai protective resistance and serving as a coupling between said timer and said shaft. I In testimony, whereof,- I have hereunto sulliscribed my name this 21'st day of March, '80'" 190. h

EGMONT MAX roRMIN.

Witnesses:

'E. B. TOMLINSON, Gno. K. WOODWOBTH. 

